Wireless communication systems are widely deployed to provide various types of communication content such as, for example, voice, data, and so on. Typical wireless communication systems may be multiple-access systems capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). Examples of such multiple-access systems may include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, and the like. Additionally, the systems can conform to specifications such as third generation partnership project (3GPP), 3GPP long term evolution (LTE), ultra mobile broadband (UMB), evolution data optimized (EV-DO), etc.
Generally, wireless multiple-access communication systems may simultaneously support communication for multiple mobile devices. Each mobile device may communicate with one or more base stations via transmissions on forward and reverse links. The forward link (or downlink) refers to the communication link from base stations to mobile devices, and the reverse link (or uplink) refers to the communication link from mobile devices to base stations. Further, communications between mobile devices and base stations may be established via single-input single-output (SISO) systems, multiple-input single-output (MISO) systems, multiple-input multiple-output (MIMO) systems, and so forth. In addition, mobile devices can communicate with other mobile devices (and/or base stations with other base stations) in peer-to-peer wireless network configurations.
To supplement conventional base stations, additional low power base stations can be deployed to provide more robust wireless coverage to mobile devices. For example, low power base stations (e.g., which can be commonly referred to as Home NodeBs or Home eNBs, collectively referred to as H(e)NBs, femto nodes, femtocell nodes, pico nodes, micro nodes, etc.) can be deployed for incremental capacity growth, richer user experience, in-building or other specific geographic coverage, and/or the like. Due to their low power, these base stations create small area cells (also referred to herein as small cells). In some configurations, such low power base stations are connected to the Internet via broadband connection (e.g., digital subscriber line (DSL) router, cable or other modem, etc.), which can provide the backhaul link to the mobile operator's network. In this regard, low power base stations are often deployed in homes, offices, etc. without consideration of a current network environment.
In a small cell deployment, due to small coverage area of these cells, an active high speed mobile device may go through frequent handovers between neighboring small cells. Additionally, even a stationary or slow moving mobile device can experience frequent handovers due to channel fading if the mobile device is present at a location where pilot signals from different small cells are about the same strength (also known as a pilot pollution region). These frequent handovers between neighboring small cells are undesirable as they can cause packet losses, leading to voice artifacts and/or packet delays and/or poor user experience, as well as increase signaling load at the neighboring small cells, macrocells, and/or the core network. Also there may be mobility problems such as connection failures or handover failures due to unplanned deployment of small cells. Moreover, an unplanned deployment may also cause a number of access terminals to experience high interference. Therefore, transmit power of small cells may need to be adjusted to handle the above concerns.